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Black Buna-N O-ring, 4.2 in inside diameter, 0.275 in cross-section, pack of five

Zoro Select

Zoro Select O-Ring 4-1/4 in Dia 1/4 in W Buna-N Black PK5

SKU CH-36H3-ZHS9J

Pack of five Buna-N O-rings with 4.2 in inside diameter, 0.275 in width and 70A durometer for -40 to 250 °F service

  • FDA-approved Buna-N material suits food-contact applications
  • Withstands -40 °F to 250 °F for wide temperature tolerance
  • 70A durometer delivers medium-hard sealing performance
  • Metal-detectable design aids contamination control in processing lines
  • Pack of five 4-1/4 in ID rings simplifies maintenance stocking

Zoro Select O-Ring 4-1/4 in Dia

This pack contains five Buna-N O-rings with a nominal inside diameter of 4 1/4 inches and a nominal width of 1/4 inch. The actual inside diameter measures 4.2 inches while the actual width is 0.275 inches. They are designed for sealing applications requiring a dash number 423 size.

Maintenance Teams and Fluid-System Builders

These rings suit technicians who need FDA-approved, metal-detectable seals for inch-measurement grooves with a medium-hard 70A durometer. They are not intended for buyers who require X-ray detectable materials or seals rated for temperatures outside the -40 to 250 degrees F range.

Medium-Hard 70A Durometer Rating

The 70A durometer defines the seal's resistance to extrusion and its ability to maintain contact pressure in dynamic or static joints. Softer compounds may extrude under system pressure while harder compounds can fail to seat properly in worn grooves. This medium-hard rating targets a broad range of hydraulic and pneumatic duties.

Highlights

  • FDA-approved Buna-N material suits food-contact applications
  • Withstands -40 °F to 250 °F for wide temperature tolerance
  • 70A durometer delivers medium-hard sealing performance
  • Metal-detectable design aids contamination control in processing lines
  • Pack of five 4-1/4 in ID rings simplifies maintenance stocking

Specifications

BrandZORO SELECT

Questions about this item

Will the 4.2 in inside diameter O-ring seal properly on a 4-1/4 in nominal shaft?

Yes, the actual 4.2 in inside diameter matches the 4-1/4 in nominal size and the 0.275 in actual width provides the correct cross-section for standard glands.

How can I confirm the Buna-N 70A material is performing after installation?

Check for zero leakage at operating pressure and verify the seal remains flexible and intact after exposure to temperatures between -40 and 250 degrees F.

Does the pack of five include any lubricant or installation tools?

The pack contains only five black Buna-N O-rings dash number 423; compatible lubricant and installation tools must be purchased separately.

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